update_deal

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Despite having annotations for idempotency (idempotentHint: true) and openWorldHint, the description adds valuable context: 'Safe to repeat — the same call twice leaves the same deal.' It also explains the side effect of setting status to 'closed' or 'lost' ('marks the deal resolved and takes it out of open pipeline revenue'), which is critical for the agent to understand the impact of the operation. It also clarifies auth requirements ('Requires an API key') and the note-replacement behavior, which the annotations do not cover.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise but information-dense. Every sentence adds value: purpose, differentiation, side effects, idempotency, auth, units, and note-replacement behavior. It fits within a few lines and is front-loaded with the main verb and resource.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no output schema, the description provides all necessary context: what fields can be changed, side effects (removing from pipeline), units, note-replacement behavior, auth requirements, and idempotency. There are no remaining ambiguities for an agent to handle this tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema covers all 4 parameters with descriptions (100% coverage), but the tool description goes beyond by explaining the units for value: 'value is in MINOR CURRENCY UNITS (2500 = $25.00)'. This is not obvious from the schema. It also clarifies the semantics of notes: 'Notes REPLACE the existing note rather than appending,' which is not in the schema. This is a great example of description adding value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Change a deal's status, value, or notes.' It uses a specific verb ('Change') and resource ('a deal'), and lists the exact fields it can modify. It also distinguishes itself from sibling 'move_deal_stage' by saying 'prefer move_deal_stage... for moving a deal along the pipeline board,' making it easy for an agent to choose between the two tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly contrasts with move_deal_stage, telling the agent when NOT to use this tool ('For moving a deal along the pipeline board prefer move_deal_stage') and what the alternative is for that use case. It also clarifies when this tool is the right choice: 'use this one for value and notes.'

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.